The proposed study will determine the interrater reliability of and diagnostic agreements between DSM-III-R and ICD-10 psychoactive substance use disorders through personal interviews using the WHO/ADAMHA Composite International Diagnostic Interview Substance Abuse Module (CIDI-AM). A pilot study conducted by the applicant found good to excellent agreement for most DSM-III-R substance use disorders. In the proposed study a sample of 125 clinical and community substance abusers will be interviewed with a test re-test design of two interviews per subject. After the second interview the interviews to determine the reason for discrepant information. The analysis will evaluate interrater reliability of DSM-III-R, and ICD-10 psychoactive substance disorders. The two systems will be compared with respect to the dependence syndrome and hazardous use and abuse. Key indicators of dependence criteria such as loss of control, craving, salience and narrowing of repertoire will be examined. Kappa statistics and 95% confidence intervals will be calculated for all comparisons. It is expected that the findings from this study will influence future decisions about the diagnostic criteria for substance abuse and dependence. * psychoactive substances include alcohol, amphetamine, cannabis, cocaine, hallucinogens, inhalants, opioids, PCP, and sedatives, hypnotics,anxiolytics.